04 Immunology

Question 1

illustration of antigen processing and presentation?

Answer 1

https://www.dropbox.com/s/6g3zee05j7k3r17/Screenshot%202013-11-07%2000.29.54.jpg

Question 2

what is the most abundant antibody in the body?

Answer 2

IgG

Question 3

which antibody is for allergic reactions, parasite infections?

Answer 3

IgE

Question 4

what are examples of type II hypersensitivity reaction?

Answer 4

ABO blood incompatibility, graves’ disease, myasthenia gravis

Question 5

what do cytotoxic T cells do?

Answer 5

recognize and attack non-self antigens attached to MHC class I receptors (eg viral gene products)

Question 6

what is type II hypersensitivity reaction mediated by?

Answer 6

IgG or IgM reacts with cell-bound antigen

Question 7

what is the structure of MHC class I?

Answer 7

single chain w 5 domains

Question 8

what do cd4 cells release?

Answer 8

release IL2, IL4

Question 9

what antibody is responsible for secondary immune response?

Answer 9

IgG

Question 10

what happens through the immunologic cascade when bacterial infections occur?

Answer 10

endocytosis by APCs (antigen presenting cells), proteins get bound to class II MHC molecules, go to cell surface, are recognized by CD4 helper T cells –> B cells which have already bound to the atigen are then activated by the CD4 helper T cells; they then produce the antibody to that antigen and are transformed to plasma cells and memory B cells.

Question 11

where are MHC class I cells located?

Answer 11

all nucleated cells

Question 12

what does IL2 do?

Answer 12

causes maturation of cytotoxic T cells

Question 13

what is type IV hypersensitivity reaction mediated by?

Answer 13

antigen stimulation of previously sensitized T cells.

Question 14

what is type I hypersensitivity mediated by?

Answer 14

eosinophils have IgE receptors for antigen and they release major basic protein

Question 15

what does MBP activate and eventually cause release of what?

Answer 15

activates mast cells and basophils, and releases histamine, serotonin, bradykinin

Question 16

what are the types of antibodies?

Answer 16

IgG, IgM, IgA, IgD, IgE

Question 17

what is the initial antibody made after exposure to antigen?

Answer 17

IgM

Question 18

what is the cell cascade when a pt gets a viral infection?

Answer 18

endogenous viral proteins produced, are bound to class I MHC, go to cell surface, recognized by CD8 cytotoxic T cells

Question 19

what are the types of MHC classes?

Answer 19

MHC class I (A,B, and C) and class II (DR, DP, DQ)

Question 20

what are examples of type I hypersensitivity reaction?

Answer 20

bee stings, peanuts, hay fever

Question 21

what do suppressor T cells do?

Answer 21

regulate CD4 and CD8 cells

Question 22

where are MHC class II cells located?

Answer 22

antigen-presenting cells (monocytes, dendrites)

Question 23

how do you test cell-mediated immunity?

Answer 23

intradermal skin test (ie TB skin test)

Question 24

what type of infections are associated with defects in cell-mediated immunity?

Answer 24

intracellular pathogens (TB, viruses)

Question 25

which antibodies fix complement?

Answer 25

IgM and IgG. They require 2 IgGs or 1 IgM

Question 26

what does IL4 do?

Answer 26

causes B-cell maturation into plasma cells

Question 27

what kind of hypersensitivity is CD4 involved in?

Answer 27

delayed-typed hypersensitivity

Question 28

what do plasma cells do?

Answer 28

secrete antibodies

Question 29

describe T and B cell activation through illustration.

Answer 29

https://www.dropbox.com/s/sogscx8m9wrjqnt/Screenshot%202013-11-07%2000.34.36.jpg

Question 30

what is MHC class I function?

Answer 30

target for cytotoxic T cells (CD8). they bind T-cell receptor

Question 31

what are the types of hypersensitivity reactions?

Answer 31

I: immediate hypersensitivity reaction (allergic) II: antibody mediated hypersensitivity reaction III: immune complex deposition hypersensitivity reaction IV: delayed-type hypersensitivity reaction

Question 32

what is special about NK cells?

Answer 32

not restricted by MHC, do not require previous exposure, do not require antigen presentation. Not considered T or B cells

Question 33

what is the name of CD4 cells?

Answer 33

helper T cells

Question 34

what do MHC class II do?

Answer 34

activate helper T (CD4) cells by binding T cell receptor and stimulates antibody formation after interaction w B cell surface IgM

Question 35

why are T cells called T cells and B cells called B?

Answer 35

Thymus and Bone

Question 36

what type of cells are part of the body's natural immunosurveillance for cancer?

Answer 36

NK cells

Question 37

what is the structure of MHC class II?

Answer 37

2 chains w 4 domains each

Question 38

what are the types of CD8 cells?

Answer 38

suppressor T cels and cytotoxic T cells

Question 39

what cells do natural killer cells recognize?

Answer 39

cells that LACK self-MHC

Question 40

which antibody is a membrane-bound receptor on B cells, serving as an antigen receptor?

Answer 40

IgD

Question 41

what are examples of type III hypersensitivity reaction?

Answer 41

serum sickness, SLE

Question 42

what makes B cells become plasma cells?

Answer 42

IL4 from T cells

Question 43

what is type III hypersensitivity reaction mediated by?

Answer 43

immune complex deposition

Question 44

which antibody gives newborn protection by crossing through placenta?

Answer 44

IgG

Question 45

what antibody is found in secretions? where else is it found?

Answer 45

IgA. found in peyer's patches in gut, breast milk (for newborns), prevents microbial adherence and invasion in gut.

Question 46

what is delayed type hypersensitivity?

Answer 46

brings in inflammatory cells by chemokine secretion

Question 47

what part of the antibody is recognized by PMNs and macrophages?

Answer 47

constant region

Question 48

which antibodies are opsonins?

Answer 48

IgM and IgG

Question 49

what is the difference between polyclonal and monoclonal antibodies?

Answer 49

polyclonal has multiple binding sites to the antigen at multiple epitopes. monoclonal has only 1 binding site to 1 epitope

Question 50

what is the largest antibody?

Answer 50

IgM. Has 5 domains (10 binding sites)

Question 51

what part of the antibody does antigen recognition?

Answer 51

variable region

Question 52

when do you give tetanus immune globulin?

Answer 52

give only with tetanus-prone wounds in pts who have not been immunized or if immunization status is unknown

Question 53

what cell is the major source of histamine in the tissue?

Answer 53

mast cell

Question 54

what is an immunologic chimera?

Answer 54

2 different cell lines in one individual (eg bone marrow transplant pts)

Question 55

what are examples of delayed-typed hypersensitivity reaction?

Answer 55

TB skin test (PPD), contact dermatitis

Question 56

what are the secondary lymphoid organs?

Answer 56

spleen and lymph nodes

Question 57

what are tetanus prone wounds?

Answer 57

(> 6 hrs old, obvious contamination and devitalized tissue; crush, burn, frostbite, or missile injuries

Question 58

what cytokine has shown success for melanoma?

Answer 58

IL-2

Question 59

what are the primary lymphoid organs?

Answer 59

liver, bone, thymus

Question 60

what cell is the major source of histamine in the blood?

Answer 60

basophils

Question 61

what does IL2 do to tumors?

Answer 61

converts lymphocytes to lymphokine-activated killer (LAK) cells by enhancing their immune response to tumor

Question 62

what cytokine converts lymphocytes to tumor infiltrating lymphocytes?

Answer 62

IL-2

Question 63

when do you give tetanus toxoid?

Answer 63

in non tetanus prone wounds: only if pt has received < 3 doses or tetanus status is unknown in tetanus prone wounds: always give tetanus toxoid unless >= 3 doses and it has been < 5 years since last booster